The present invention relates to an apparatus for evaluating a performance of a plasma polymerized polymer layer using an ultraviolet (UV) spectrometer.
Conventionally, in order to modify a surface of a substrate by synthesizing a polymer, an ion implantation or an ion irradiation method using a high energy (high keV to low MeV) is used, or a polymer is deposited on a surface of a substrate by using an ion beam sputtering deposition which uses an ion source generating particles of a comparatively low energy (O to a few keV), by using a multi-ion beam deposition or by using an ion-assisted deposition.
However, such a method has disadvantages in that it requires a comparatively high energy and a high vacuum state, it is not easy to synthesize a polymer and cost requirements are high.
Thus, there has been proposed a surface modification method using plasma which is capable of forming polymer on the substrate at a low energy and in a low vacuum state.
In this method, a reactive gas including monomers of a material to be synthesized is introduced into a chamber which is placed under vacuum. The gas is then discharged by a direct current or a high frequency by using a power supply unit. Then, plasma of the reactive gas is generated, of which predetermined ions are moved to the substrate or to an electrode, to synthesize a certain polymer thereon.
At this time, various chemical combinations are made depending on the type of reactive gas, a mixed ratio thereof, a direct current/voltage, a high frequency power or a deposition time, etc., so that the surface of the substrate can be modified without affecting the inherent characteristic of the substrate, by depositing polymers having required physical properties such as surface strength, adhesion/adsorption, and hydrophilicity/hydrophobicity on the surface of a substrate.
FIG. 1 shows a schematic view showing the construction of a plasma polymerization apparatus in accordance with the background art.
As shown in FIG. 1, the plasma polymerization is performed in a polymerizing chamber 1 which includes a gas inlet 7, a gas outlet 8, a vacuum pump 9 and an electrode 3 generating a potential difference for the substrate.
For polymerization, the vacuum pump 9 of the polymerizing chamber 1 is actuated to obtain a desired vacuum degree, a reactive gas is introduced through the gas inlet 7, the substrate 2 is conveyed to a winding chamber 5 by passing an unwinding chamber 4 and a roller 6, during which a voltage is applied to the electrode of the polymerizing chamber 1 to generate a potential difference to the substrate 2. Then, as the reactive gas is induced to the surface of the substrate 2, plasma is discharged.
When the plasma is discharged, the molecular bonding of the reactive gases are cut off, and the cut-off bonding and activated positive ions or negative ions are bonded to form a polymer on the surface of the substrate 2 proceeding between the electrodes.
However, up till now, no method has been proposed to effectively evaluate the performance of a polymer layer polymerized on the surface of the substrate 2 which is consecutively modified and wound in a coil form in the winding chamber 5.
Therefore, an object of the present invention is to provide an apparatus for evaluating a performance of a polymer layer formed on a surface after being consecutively processed without affecting physical and chemical properties of the polymer layer.
Another object of the present invention is to provide an apparatus for effectively evaluating a performance of a polymer layer without affecting a process parameter such as a degree of vacuum of a polymerizing chamber.
In order to achieve the above objects, there is provided an apparatus for evaluating a performance of a plasma-polymerized polymer layer using a UV spectrometer, comprising a polymerizing chamber for forming a polymerized polymer layer on a surface of a substrate by plasma discharging, a UV probe mounted contactless to the polymerized polymer layer formed in the polymerizing chamber and transmitting/receiving UV to and from the polymer layer and a UV spectrometer analyzing a signal inputted from the UV probe.
The UV probe is preferably installed to be sealed from the chamber and installed over a transmission part to transmit the UV.
More preferably, the chamber has a hole in which the transmission part is installed to be sealed to the chamber.
Additionally, an UV probe support means for adjusting the level of the UV probe is additionally installed at an outer wall of the chamber.
Moreover, the transmission part is made of crystal of calcium fluoride.